Enabling 2 GB Large Pages on Solaris 10

Few facts:

• - 8 KB is the default page size on Solaris 10 and 11 as of this writing
• - both hardware and software must have support for 2 GB large pages
• - SPARC T4 hardware is capable of supporting 2 GB pages
• - Solaris 11 kernel has in-built support for 2 GB pages
• - Solaris 10 has no default support for 2 GB pages
• - Memory intensive 64-bit applications may benefit the most from using 2 GB pages

Prerequisites:
OS: Solaris 10 8/11 (Update 10) or later
Hardware: SPARC T4. eg., SPARC T4-1, T4-2 or T4-4

Steps to enable 2 GB large pages on Solaris 10:

1. Install the latest kernel patch or ensure that 147440-04 or later was installed
   
   • Check the patch download instructions
2. Add the following line to /etc/system and reboot
   • set max_uheap_lpsize=0x80000000
3. Finally check the output of the following command when the system is back online
   • pagesize -a
   eg.,

   % pagesize -a
   8192  <-- i="">8K

65536 <-- i="">64K 4194304 <-- i="">4M 268435456 <-- i="">256M 2147483648 <-- i="">2G % uname -a SunOS jar-jar 5.10 Generic_147440-21 sun4v sparc sun4v